package cn.tedu.sp06.fb;

import cn.tedu.web.util.JsonResult;
import org.springframework.cloud.netflix.zuul.filters.route.FallbackProvider;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
@Component
public class OrderFB implements FallbackProvider {
    /**针对哪个模块应用当前降级类
     * item-service：只针对商品降级
     *  *：对所用模块进行降级
     *  null：对所用模块进行降级*/

    @Override
    public String getRoute() {
        return "order-service";
    }
    //发送给客户端的降级响应
    @Override
    public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
        return new ClientHttpResponse() {
            //HttpStatus对象，封装状态码和状态文本   比如 200  ok
            @Override
            public HttpStatus getStatusCode() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR;//返回服务器内部错误
            }

            @Override   //返回状态码
            public int getRawStatusCode() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR.value();
            }

            @Override//返回状态文本
            public String getStatusText() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR.getReasonPhrase();
            }

            @Override
            public void close() {

            }

            @Override
            public InputStream getBody() throws IOException {
                //JsonResult -{code：500，msg：调用后台服务失败，data：null}
                String json = JsonResult.build().code(500).msg("调用后台服务失败").toString();
                return new ByteArrayInputStream(json.getBytes(StandardCharsets.UTF_8));
            }

            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders h = new HttpHeaders();
                h.set("Content-Type","application/json;charset=UTF-8");
                return h;
            }
        };
    }
}
